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Course Topics:
This 23.75-hour review and update in the areas of clinical immunology, microbiology, and infectious diseases is intended to improve knowledge about the pathogenesis and clinical manifestations of infectious diseases, immunological mechanisms of disease and disease prevention, appropriate approaches to the diagnosis of infections and immunologic disorders, and utilization of the clinical microbiology and immunology laboratory, including selection and interpretation of results.

This course will provide a forum for the exchange of ideas dealing with microbial infections as well as immunity to infectious diseases and immunologic disorders. Faculty consists of clinicians involved in patient care, pathologists, and clinical laboratory scientists. Discussion of timely topics by faculty and participants assures that this course will be informative, interesting, and relevant.

(1) We are constantly looking for Reviewers for each of our 7,000 topics, which we plan to update every 1-2 years. In particular, we are looking for reviewers of Soft Tissue Tumors and various Stains. Visit our newly updated Instructions for Reviewers page for more information.

(2) The Table of Contents of our Stains chapter now includes all 360 stains / biomarkers described in the chapter. The CD Markers chapter contains an additional 260 markers. We update these pages regularly, but let us know of any new markers we should include or other changes we should make.

An 81 year old man had a painless tumor of his left great toe, which was excised. Macroscopically, the tumor was well-circumscribed, measured 4 x 3 x 2.5 cm and was located in the subcutis.

Micro images:

What is your diagnosis?

Diagnosis:

Symplastic glomus tumor

Discussion:

The tumor was encapsulated and composed of solid sheets of cells separated by vessels of varying size and lined with normal appearing, CD34+ endothelium. The neoplastic cells showed pronounced nuclear pleomorphism, hyperchromasia and occasional intranuclear inclusions. Mitotic activity was sparse, up to 2 mitoses/50 HPF, but the Ki-67 proliferative rate was about 25%. There were no atypical mitotic figures, but areas of necrosis were present. Tumor cells were diffusely immunoreactive for smooth muscle actin (SMA), vimentin and desmin.